Strawson developed his descriptive metaphysics in close relation to Kant’s metaphysics of experience which can be understood as a particular version of descriptive metaphysics. At the same time, Strawson rejects the foundations of Kant’s version of descriptive metaphysics which, according to him, is a species of psychology. His argument against Kant’s conception of subject, or of the ‘I’, can be found in his conception of person. A closer scrutiny of this conception of Strawson can, however, reveal that it is not comprehensive enough compared with that of Kant. Speaking with Kant, Strawson understands the part of being ‘I’ which can be known via self-knowledge but he fails to appreciate the second part of being ‘I’, namely self-consciousness. A comparison of Strawson’s conception with Kant’s conception of being ‘I’ reveals its systematic shortcomings that rather support, against Strawson’s purpose, Kant’s version of descriptive metaphysics as a theory of subjectivity